A technology of a lubricant feed mechanism for an engine has been known by which lubricant is fed to a cam of a valve gear through a cylinder head, a camshaft, a cam cap, and an oil feed member. Examples include Patent Document 1.
A lubricant feed mechanism for an engine described in Patent Document 1 includes a cylinder head having a bearing, a camshaft rotatably supported by the bearing, a cam cap fixedly attached to the cylinder head from the upper side to hold the camshaft therewith, and a cam shower pipe connected to an upper portion of the cam cap.
Further, the lubricant feed mechanism includes a communicating oil passage from an oil gallery of the cylinder head to the camshaft (bearing), an oil passage penetrating the camshaft (cam journal), and a communicating oil passage that is provided in the cam cap and connects the camshaft to the cam shower pipe.
In the lubricant feed mechanism thus configured, lubricant that circulates through the oil gallery is fed to a plurality of cams of a valve gear through the cylinder head, the camshaft, the cam cap, and the cam shower pipe. Thus, lubricant of a substantially equal amount can be fed to the plurality of cams by extracting lubricant from the oil gallery of a relatively large diameter, i.e., with a less pressure loss.
However, according to the technology described in Patent Document 1, the cam shower pipe for feeding lubricant to the cams needs to be folded or brazed appropriately, and a process for making an aperture in the cam shower pipe is also necessary. Thus, the technology described in Patent Document 1 has a disadvantage of high manufacturing cost.